Eddy current damping is generated in accordance with the basic principle in which when a conductor plate in a local magnetic field cuts magnetic lines of force, eddy current is generated in the conductor plate, and the eddy current in turn generates a new magnetic field having a direction opposite to that of the original magnetic field, and thus a damping force, which hinders a relative motion of the original magnetic field and the conductor plate, is formed therebetween, and meanwhile, under a resistance effect of the conductor plate, kinetic energy obtained by the conductor plate is converted by means of the eddy current into heat energy for dissipation. If being connected with a vibrating structure, the conductor plate may produce effects of structural damping and energy dissipation, forming an eddy current damper. Different from some damping devices commonly used in the field of structural vibration control, the eddy current damper dissipates energy without using mechanical friction, and here problems of fluid leakage and sealing do not occur since no working fluid is used; furthermore, it has advantages such as high reliability, excellent durability and relatively simple structure, and is therefore particularly suitable for use in a working environment requiring a long fatigue life and being not easy for maintenance.
An efficiency index of the damper refers to a ratio of a damping force generated by the damper at a rated speed to its own weight. The eddy current damping itself has a low energy dissipation density, and thus causes the efficiency index of the eddy current damper directly using an axial relative motion mode to be low, which is the main reason why the eddy current damping is hindered from being applied to large-scale engineering structures for a long time. The Chinese Patent Application with Publication Number of CN103821861A greatly improves the efficiency index of the eddy current damper by use of screw drive, however, it is difficult for the rotating disk structure therein to meet an anti-vibration requirement for a speed index of less than 1.